Apparatus for producing oil



March 19, 1943. v. H. GILLILAND Er AL 2,194,017

APPARATUS FOR PRODUCING OIL Filtad Oct. 24, 1936 2 Sheets-Sheet 1 Mah 19, 1940- V.MH. GILLILAND Er AL 2,194,017

APPARATUS FOR PRODUGING OIL Filed OCT.. 24, ,1936 2 Sheets-Sheet 2 l l 36V" E im 47 5/ 5 43 @y/15. 'J//z/fm 5` l Jaim James ra/zam,

Patented Mar. 19, 1940 PATENT OFFICE APPARATUS FOR PRODUCING OIL Virgil H. Gilliland and John James Graham, Conroe, Tex., assignors of Aone-fifth to T. F. Green, Jr., Conroe, Tex.

` Appncation october 24, 1936, vserial No. 107,492

3 Claims.

This invention relates generally to the production of petroleum and more particularly to the production of petroleum from' wells'by pump.-

, ing. 5. As islwell known, the initial stages of commercial development of petroleum deposits includes flowing the oil from the deposit to the surface in a well, the upward flow of the oil being caused by tremendous pressures effec- 10 tive upon the oil and gas in the oil-bearing formation of the deposit. Due to its compressible nature, the gas in the 4deposit comprises the force producing the expulsion ,ofthe oil from the deposit, and flow of oil in ,the well continues until ll suflicient of the gas and oil comprising the deposit have escaped to result Ain a diminution of the natural pressure tothe point where it is no longer adequate to raise the column of petroleum to the top of the well; thereupon further re- 2Q covery of the petroleum necessitates pumping.

During the flow of the well the energy available to lift the oil may be considered that produced by the expansion of the gas during its removal from the Well. The gas always tends to 35 pass through the formation more easily than the oil and reaches the well more rapidly, having'a tendency to leave the oil behind in the formation. Ordinarily, there is a. large initial excess of energy available in the gaspresent, but sooner 30 or later the quantity of gas available decreases. Even after pumping is resorted to, it is found that the, reduced gas pressure facilitates the pumping operation and the conveyance of the oil in the formation toward theWell. It will 35 therefore be understood that conservation of the gas in the formation in order to preserve its pressure eect is of great importance, and it is therefore an important object of the present invention' to provide for the conservation of the gas :any in the formation while pumping the oil froml the well. Experience has shown that by the time pumping is necessary the gas content has been reducedzfar in excess of the reduction of the oil .4,5E content o-f the deposit, and this to such an extent that bythe time the escape of gas from the sand has removed the pressure forcing the oil into the well, a large proportion of the total oil in the formation, as much as 50% for example, 5o can not be recovered without pumping. During pumping, the production of oil from the deposit. tends to slump rapidly due to the diiculty experienced heretofore in the industry in holding back the gas while pumping the oil.

It has been f'oun'd that when a well is operated Flowing wells, being actuated 'by gas under 45 so as to control the rate of ilow of oil and gas to some point below that representative of the total capacity of the pump, the result is to increase the life of the well and increase the proportion of oil recovered. 5

Recent developments in the economics of conservation have taken the form of limiting production over large areas upon the basis of gasoilv ratio, and it is another object of the present invention to enable the convenient regulation 'of theflow of gas from the well with a view to reducing it to that amount capable of being absorbed in the oil.

It has been found during pumping operations that blow-offs of free gas in the well may be frel5 quently`e'xperienced, and these blow-offs have been known to occur at either regular or irregular. periods and in regular or in unpredictable degrees of intensity. Blow-offs of gas always reduce the production of oil obtained from the Well inasmuchfas they at least empty the well of oil and frequently waste the oil by spraying it from the well head in such manner that it can not be recovered, and further deleteriously affect the constructionand operation of the pumping ap-v g5 paratus by causing the pump to operate dry over long periods of time. In addition to the. loss of production necessitated by the pumping in oil-empty tubing, such blow-,offs frequently` necessitate the pulling of the well and repair:` before production can be resumed. When it is't recalled that the average pulling operationre-j. quires between four and ten hours during whichno production of oil from the well is possib 1eitv will be obvious that control of `the movement off free gas through the well is of'great. economic importance from the standpoints both of labor5 and operating expense in production.4`

It is therefore another object of the present invention to control the production from a 40 pumped well in sueh manner that the movement of free gas in the formation and the well may be controlled to prevent periodic or irregular gas blow-oils.

pressure are productive of a liquid product whichc l includes a great deal of mixed or occluded gas, and attempts have been made to handle the oil while conserving the gas pressure of the Well by passing the oil through restricted` chokes 5 0 in the tubing and through a gas separator at the surface.

Heretofore, gas anchors have been designed with a view to separating the entrained or occluded gas from the oil and feeding the oil to the well head while attempting to repocket the Due to the greatly lessened gas pressure in the` formation at a well being produced by pumping, the oil obtainable from a pumped Well is much less volatile than that obtained from a flowing well to an extent that it ordinarily contains no gas dissolved in the oil as a liquid phase, or gas liquified at formation pressure. Such oil does, however, contain appreciable quantities of gas which is physically mixed in the oil and adapted to be released therefrom by gravity separation. Since this proportion of the gasis but a small fraction of that quantity found combined as a liquid phase in a liquid phase, as obtained from a flowing well, it has been discovered that use of the gravity separation method is not productive of separation of gas in quantities important from the standpoint of conservation.

The blow-offs frequently encountered in pumped wells are caused by the moving toward the well from the formation of volumes of free gas of the same physical character as thatseparated by gravity gas anchors, and there is strong reason to believe that the gas separated in gravity gas anchors is merely a contributing factor in the eventual production of gas blow-offs.

It is therefore another object of the present invention to provide for economical and efficient production of oil whereby the oil is pumped from the bottom of the hole without requiring separation of gas from the oil or incurring the risk of Vaccumulating volumes of free gas adjacent the bottom.

Recently, extensive experiments have been conducted and conclusions developed establishing that the problem of gas control at pumped wells has been treated improperly heretofore, and that instead of attempting to conserve the gas pressure in the formation by separating gas from the oil and attempting to repocket it, the proper technique to be followed comprises mixing the gas with the oil being pumped toward the surface. This involves not only an increased absorption of free gas by the oil which thereby carries it from the well to eliminate tendency toward gas blowoffs; but it enables the further advantage that the mixing operation embodies a coincident choking effect upon the passage of the fluid. Results have indicated that the consequence of these inter-related functions has been to insure that the total product of the well is an oil of uniform character which contains its maximum mechanically absorbed charge of gas. The amount of gas liberated from the formation is thus materially reduced, and the desired gas-oil ratio in the formation is easily and controllably maintained.

It is therefore another object of'the present invention to conveniently, economically, and reliably control the gas and oil yield of a formation.

In the control' of owing oil, the higher quantities of gas mixed in the oil, such as in a liquid phase relationship, are customarily separated out at the surface by passing the yield through a conventional gas separator, and the separated gas is ordinarily permitted to waste into the atmosphere while the oil goes into storage. The carrying over of this thought of lgas separation into the art of producing by pumping has apparently involved needless waste of the gas sought to be repocketed inasmuch as separation apparently has not accomplished its object of preventing blowoffs, and it removed from the oil valuable entrained gas. The product of a pumped well from which gas has been separated therefore has been made unnecessarily low in A. P. I. gravity, without obtaining any compensating gain in operating efliciency.

It is a further object of the present invention to treat the oil during pumping in such manner as to produce a yield of a distillate type readily characterized by a A. P. I. gravity raised from l to 5 degrees above that otherwise obtainable.

l 'Ihis is accomplished, for example, by mixing the paratus containing provision for .handling the oil as it is pumped whereby not only is its flow choked to conserve the formation pressure, but its A. P. I. gravity is raised to a valuably high rating considerably above that which would otherwise characterize the pumped product of the formation. An important object of the invention is the provision of a beater which is actuated by the liquid passing therethrough, thereby obviating the necessity for extraneous devices for obtaining the beater action.

Relatively small diameters of casing and tubing are employed in a deep Well of the order of four or five thousand feet and the problem of positioning pumps and gas anchors therein is extremely technical. The safety, durability, and efficiency of the plant and facility in its installation and operation are thereby enhanced by constructing the present gas anchor with a smooth continuous exterior thereby eliminating protuberances and the likelihood of such protuberances contacting the Walls of the casing or other apparatus with deleterious consequences. Important among the novel features of the apparatus is the provision of a gas anchor assembled of sections, and the inclusion therein of specially designed perforated bull-plugs of varying types, as for the passing, diversion, and spraying of the liquid passing therethrough.

With the foregoing and other objects in view which will be made manifest in the following detailed description and pointed out in the appended claims, reference is made to the accompanying drawings of illustrative embodiments of the invention wherein Fig. 1 is a vertical section, somewhat diagrammatic, through an oil well, showing the improved gas anchor and its disposition and operation for accomplishing the novel methods;

Fig. 2 is a view similar to Fig. 1 showing the gas anchor attached to the tubing rather than to the pump;

Fig. 3 is an enlarged elevational view of the gas anchor; l

Fig. 4 is a vertical section corresponding to Fig. 3 of the gas anchor;

Fig: 5 is a horizontal section taken on the line 5-5 of Fig. 4;

Fig. 6 is a horizontal section taken on the line 6 6 of Fig. 4;

Fig. '7 is a horizontal section taken on the line 1-1 of Fig. 4;

Fig. 8 is a horizontal section taken on the line 8-8 of Fig. 4;

Fig. 9 is a horizontal section taken on the line 9 9 of Fig, 4;

Fig. is a horizontal section taken on the line |0||| of Fig. 4;

Fig. 11 is a horizontal section taken on the line of Fig. 4;

Fig. 12 is a horizontal section taken on the line |2--I2 of Fig. 4; and

Fig. 13 is a bottom plan view of the gas anchor shown in Fig. 3.

Referring to the accompanying drawings wherein similar reference numerals designate similar parts throughout, the well hole is indicated at in which there is disposed the well casing 2|. The pump piston is indicated at 22 upon the lower end of which is mounted a conventional coupling 23 having a tapered interior providing a seat fora seating valve 24. The seating valve is shown as provided with a ball closure 26 within a case 21. The lpiston 22 is enclosed by a cylinder 28 which is reciprocated on the piston to pump the oil therethrough. All of the above described structure is conventional in the ordinary well pump.

Instead of the conventional mudanchor, the pump is shown equipped with a gas anchor 29 which may extend to the bottom ofthe well adjacent to a screen 3|. It will be understood that the operation of the pump carries the oil to the well head'32, having connected thereto conduit 33 for discharging the oil into'the storage tank 34. The pump is actuated from the head by means of the sucker rod 35 operating through the conventional stuffing box 35', sucker rod 35 being fixed to the cylinder 28. The fixed piston 22 is provided wth passageways 25-25 and the upper end of the cylinder 28 has corresponding passageways -30 through which the iiuid flows into tubing 40 during the pumping operation, the apertures 30 having ball valves 45-45 for sealing the apertures during the return stroke of the cylinder along tubing 48.

As shown'clearly in Fig. 4, the gas anchor constituting means whereby my invention may be practiced is a tubular structure having a smooth exterior assembled by uniting end to end corresponding sections, 36, 31, 38, and 39, respectively. The sections 36 to 39 inclusive are pipe of hardened steel and have threaded portions 4| whereby they may be assembled to form a singletube having a smooth continuous exterior and a common coaxial bore through which the fluid recovered from the well is pumped.

The invention will best be understood by describing the sections 36 to 38 inclusive consecutively and in the order of their operation upon the fluid extracted from the well. For example,

one end 36 of the gas anchor-includes an entrance or mud anchor section adapted to lie at the bottom of the gas anchor when the latter is in the vertical position of employment. Section 36 is slotted at 42 and tapered at 43 to form a straining aperture 44 including lateral contrib,- uting apertures 46, 46 through which the fluid enters. Along the shank of the cylindrical section 36 are spaced apertures 41 intowhich the fluid enters, the apertures constituting the section somewhat as a sieve and calculated to'provide a flow of fluid therethrough while eifectually excluding particles deleteriously large. It will be obvious that as the gas ows into the section 36 through the apertures 44 or 41, a substantial quantity of the gas comprising the surrounding gas envelope willbe entrained therewith or carried in gaseous state into the section 36 and upwardly therethrough as bubbles in the oil. The pressure, suction, and turbulence of said passage necessarily results in a mixing of the gas so carried with the oil.

At the upper extremity of the section 36 same is provided with a novel type of bull-plug 46 fast to the inner surfacel of the section 36 and projecting axially thereabove. Thev bull-plug 48 is formed with an eccentric outlet aperture 49 oi a highly restricted order in order that the quantity of fluid conveyed from the well by the ordi'4 nary pump suction will be choked by being obliged to pass through the aperture 49 thereby contributing further toward the mixing of the gas and oil and materially operating to chokev the iiuid flow through the well and, by holding back the oil, consequently helping additionally to maintain the gas at the bottom hole and in the formation.

The section 31 ,constitutes an important ele- I ment o f the invention and includes the means for beating the fluid as the substantial means for accomplishing the efficient result of the invention. Section 31 is, like the other gas anchor sections, hollow to contain a rigidly xed tubular cage 5|. The tubular cage comprises opposite, end discs 52 and 53 rigidly inter-connected by strips 54. Inwardly from each disc 52 and 53 there are fixed other discs 56 and 51. Fast in the discs 56 and 51 at the center line of the gas anchor is rotatably journaled a shaft 58 having reduced ends'59-59 bearing in the discs 56 and 51. Supported uponthe shaft 58 at diametrically opposite points are parallel blades 6| adapted to be rotated with the shaft 58.

'Ihe blades 6|-6I are twisted to spiral formatlon and are sufficiently Wide to extend from the shaft 58 approximately to the periphery of'the discs 56 and 51. Upper discs 52 and 56 ,are provided respectively with aligned holes 62 and 63 which in turn are located as to be in longitudinal alignment with the outer edge of the spiral blades 6|. Lower discs 53 and 51 are formed with aligned holes 64 and 66 also in longitudinal alignment with the outer edge of .the spiral blades 6| but diametrically opposite from the holes in the discs 52 and 56. It willbe understood that the shaft 58 and the blades 6| aflixed thereto rotate on the axis of the ygas anchor and with respect to the strips and disc portions of the cage. No auxiliary or extraneous mechanism is required to drive the spiral blades comprising the beater', the motive power being supplied by the pump which draws the oil and a portion of the surrounding gas upwardly during the pumping operation, the iiuid passing through the bull-plug 48 and rst through-the lower holes 64 and 66. These holes being aligned with the edges of the spiral blades thrust the stream of fluid thereupon the fluid tends to flow along the blades thus producing a rotation of the shaft 58. The full force of the stream is directed upon the rotary beater, the stream tending to move diametrically across the cage to pass upwardly through the upper holes 62 and v63 of the upper discs. The suction of the pump exercises a powerful force upon the current forcing it through the disc .apertures and upon the blades to propel the beater to extremely rapid revolution, thus whipping the iluid passing therethrough to produce a union of the gas-and oil in a highly mixed state. It will be .understood that the mixing is sufciently, pronounced jthat the gas content of the oil is materially increased, the extent of such absorption, depending upon the characteristics of the gas and oil, being such as to raise the A. P. I. gravity of theoil from 1 to 5 degrees.

Due to the lodestone effect commonly encountered at pumping depths the rotating element such as the shaft 58 is preferably constructed of brass or copper or similar non-magnetic material..

The section 31 is provided with a bull-plug 81 similar to the bull-plug 48 by having its aperture 88 eccentrically disposed opposite from that of the bull-plug 48. The highly mixed oil with its maximum absorption charge of gas is drawn through the bull-plug 81, it being understood that the latter, together with the reduced aperture 49 of the bull-plug 48 and the reduced apertures 82 to 61 exercise a high choking effect thereon tending to retain the oil in the beater for as long a time as is required to obtain maximum gas absorption.

' The oil is then drawn upwardly into section 38 where it is subjected to additional mixing. The

section 38 is provided with a stationary type mixer consisting of a cage 10 fast to the inner surface of the section and constructed of four spaced ribs 1I, 1| to which are secured four spaced discs 12, 13, 14, and 15. Section 38 constitutes an important aspect of the invention in that it is an effective choke for the mixture drawn there through. The upper and lower discs 12 and 15 are formed with a plurality of spaced apertures 16, 16, such apertures being preferably six in number in each disc. The intermediate discs 13 and 14 cooperate in producing the choking effect being provided with spaced apertures 11, 11, four such apertures being in each disc. It will be understood that as the mixed fluid is brought successively through the perforated discs the fluid is directed through the staggered apertures 16 and 11. In addition to choking the oil the perforator or choke section 38 assists in maintaining the high degree of mixture resulting from passages through the beater section 31.

The perforater section 38 is provided with a bull-plug 18 of still another novel type of construction. Instead of having the eccentric apertures such as the bull-plugs 48 and 61 it is slotted and turned to form a spray nozzle 19. When the choked mixture is forced therethrough it is advanced therefrom in a vapor or spray.

The spray mixture is then drawn through the section 39 designated as the whipper section. A whipper 8| is fixed within the section 39 and includes a cage 82 consisting of longitudinal strips 83 interconnecting spaced rigid discs 84, 85, and 86. Rotatably journaled in diametrically opposed strips 83 between the discs 85 and 86 is a rotatable horizontal shaft 81 to Which is xed oppositely extending whipper blades 88-88. The whipper blades comprise a disc but slightly smaller in diameter than the cage so that they extend substantially entirely across the bore when horizontally disposed. A second whipper blade 89 is fixed to a horizontal revolvable shaft 90 journaled in the strips 83 between the discs 84 and 85 corresponding in dimension and position with the blade 88. The discs 84. 85, and 86 are perforated to permit the passage of the spray or misted mixture therethrough and preferably the perforations are so located with respect to the blades 88 and 89 to insure that the forced jet of spray will impinge upon the blades adjacent their periphery in order to produce a rapid spinning thereof. Accordingly the lower disc 86 is perforated at 92 to the right of the axis; the disc 85 is perforated at 93 to the left of the axis; and the disc 84 is perforated at 94 preferably eccentrically. By reference to Fig. 4 it will be observed that the jet of spray entering through perforation 92 will rotate the blade 88 in a counter-clockwise direction in passing toward perforation 93 and thereafter the jetted spray will engage blade 89, rotating it in a clockwise direction in passing toward perforation 94. Preferably the rotating elements of the whipper are formed of non-magnetic materials such as copper or brass in order to avoid the lodestone effect referred to above. In order to insure a clear path for the spray and initiate rotation of the blades 88 and 89, one each of the pairs of blades 88 and 89 is made heavier than its complement in order that the blades, when idle, will not lie in the horizontal. Any balancing of the blades 88 and 89 in dead center choking position is thereby prevented.

The oil after it is drawn through the whipper is an intimate mixture of gas and oil in nely divided spray form having been mixed both before and after its separation to spray condition. The product is thendrawn from the gas anchor upwardly to the top of the well where it passes through. the head and conduit 33 to any suitable storage tank 34. Tests of the contents of the storage tank 34 will be found invariably to establish that the oil produced by the described method and apparatus has an A. P. I. gravity greater by from one to ve degrees than that A. P. I. gravity which would characterize the product of the same well through the practice of old methods.

Although the beater section described above importantly contributes to the advantageous conduct of the method and the beneficial results obtained thereby, it will be understood that each of the sections of the gas anchor performs, in varying degrees, as indicated above, choking and mixing functions.

If desired instead of connecting the gas anchor of the present invention to the pump as indicated in Fig. l, it may be connected to the tubing as illustrated in Fig. 2 wherein the gas anchor 29 is shown internally threaded as at IUI and thereby connected to the lower end of the Well tubing |92. Due to the mud anchor type of construction employed in the section 36 as described above, it is not essential to employ a strainer or a mud anchor per se with the universal gas anchor 29, the design and operation having frequently been tested and found to function for the transmissal of any entrained sand or solid particles ordinarily found to pass through the strainer.

Preferably all of the moving elements described above in the sections 31 and 39 are made of a non-magnetic material in order to avoid their being deleteriously affected in their operation by lodestone influence.

We claim:

l. Apparatus for operating an oil Well which includes a pump for advancing the oil from the bottom hole along a predetermined path, a gas anchor below said pump communicating therewith and having opposite inlet and outlet apertures through which said oil advances, means between said inlet and outlet apertures for beating the oil under substantially bottom-hole pressure conditions to intimately mix well-gas therein while advancing the oil along said predetermined path including means for choking the gas-added oil, means-for further choking the gas-added oil by dividing a body thereof into a plurality of separate streams, and means for atomizing the oil to further mix the gas therewith, said included means arranged to act successively on the oil.

2. In an apparatus for producing oil, a pump, a tubular gas-anchor assembly delivering to said pump and having spaced inlet and outlet apertures, said assembly having spaced whipping. choking and beating elements therein between said inlet and outlet apertures, said choking element being disposed between said whipping and beating elements, one of said whipping and beating elements being revolvable on an axis transverse to the axis of the tubular assembly and the other of said Whipping and beating elements being revolvable on an axis transverse to that of the other Whipping and beating element, said whipping and beating elements being pivotally mounted for rotation by passage of the oil therethrough.

3. In an apparatus for producing oil, a pump, a cylindrical tubing in communication therewith, a gas anchor below said pump and in communication with said tubing, said gas anchor having beating and Whipping means for successively engaging oil and gas from the producing formation to form an intimate mixture thereof, said beating and whipping means being rotatable and composed of non-magnetic materials to avoid lodestone inuence.

VIRGIL H. GIILILAND. JOHN JAMES GRAHAM. 

